Method of preparing textile materials



Nov. 18, 1941. w, WHITEHEAD 2,262,872

METHOD OF PREPARING TEXTILE MATERIALS Filed June 1, 1938 FILAMENTSFORMED ARE. OF DIFFERENT DENIERS FILAMENTS OF SMALLER DENIER ARE BROKENINVENTOR vvnum'n Whifehead Y 1 My WW- ATTORNEYS Patented Nov. 18, 1941METHOD OF PREPARING TEXTILE MATERIALS William Whitehead, Cumberland,Md., assignor to Celanese Corporation of America, a. corporation ofDelaware Application June 1, 1938, Serial No. 211,205

18 Claims. (CI. 1854) This invention relates to the manufacture ofyarns, and particularly yarns of cellulose acetate or other organicderivative of cellulose, having the appearance of spun yarn or yarn madefrom staple fiber, and relates also to fabrics made from such yarns.

This application is a continuation-in-part of my application S. No.205,990, filed May 4, 1938.

An object of the invention is the economic production of staplized yarn,i. e. one having the appearance of being composed of short lengths offiber spun into a yarn and which is formed of continuous filamentswhich, after the filaments are grouped together to form a yarn, aresubjected to an operation to break the continuity of some, but not all,of the filaments associated in the yarn, so that the resulting yarn hasa number of broken ends which give it, when twisted, the appearance of aspun yarn. Another object of the invention is to reduce the number ofsteps formerly necessary to produce such a yarn. A still further objectof the invention is the production of a more uniform and strongerstaplized yarn which, therefore, may be knitted into circular knitfabrics with less presser marks, holes and other faults. A still furtherobject of the invention is the product of a staplized yarn which knitsinto a fabric characterized by having softer hand. Other objects of theinvention will appear from the following detailed description.

Imitation spun yarn, or staplized yarn, .has been made by processeswhere some filaments of a continuous filament yarn are broken to breakthe continuity of same. Such a process is described in U. S. Patent No.2,098,980 to Sowter. Other methods have been employed wherein some ofthe filaments of the yarn are cut or torn to produce a similar effect. Ihave now found that a yarn having the appearance of a spun yarn may beproduced more economically and at the same time stronger yet capable ofbeing knitted into a softer fabric.

In accordance with my invention, I spin a yarn from a solution of asuitable organic derivative of cellulose in a solvent therefor byextruding the solution through a jet into a drying atmosphere or aprecipitating medium, under such conditions that theresulting yarncontains at least two sizes of filaments. One method of accomplishingthis is to have two jets in the same cabinet, one jet having fine holesand the other jet having coarser holes both fed by the same pump. Alsotwo separate jets may be employed in the same cabinet, the jets havingthe same size holes but fed by separate pumps, where the debit of thepumps will produce different size filaments. The filaments from the twojets are led from the cabinet together and are wound on to the samebobbin. Another method of carrying my invention into eifect is toproduce one end of fine filament yarn and one end of a coarser filamentyarn in adjacent'cabinets and draw the same together by a feed roll andthen wind them on to the same bobbin. Still another method of producinga yarn in accordance with the instant invention, although this method isless desirable as it requires an additional step, is the plying togetherof a fine filament yarn and a coarser filament yarn from suitable supplypackages. The yarn containing different size filaments and While itcontains little or no twist, say under 5 to 10 turns per inch andpreferably about 1 or less turn per inch, is subjected to a staplizingaction by stretching and breaking the finer denier filaments leaving thecoarser filaments unbroken. This yarn may then be further twisted,doubled, etc. and woven, knitted or knotted into a fabric. This yarn maybe the sole yarn in the fabric or it may be used in connection withother types of yarn.

This invention aims to produce a staplized yarn of cellulose acetate orother organic derivative of cellulose. Examples of other organicderivatives of cellulose are the cellulose esters such as cellulosefo-rmate, cellulose propionate and cellulose butyrate, and the celluloseethers such as ethyl cellulose, methyl cellulose and benzyl cellulose.It is also applicable to yarns of regenerated or reconstitutedcellulose, which yarns are formed by extruding a solution of suitablecellulosic material through a jet to form substantially continuousfilaments.

Any number of filaments may be built up into a yarn, say from 20 to 200or more. These filaments may be of two different sizes or may be ofthree or more sizes, it being understood that the finer the filament themore readily it is reduced a spinning one end of 85 denier 25 filamentyarn from one jet and of denier 40 filament yarn from another jet in thesame cabinet, and

The yarn containing two or more sizes of filan ments as it issues from aspinning device or taken from a package may have the'finer 411a:

ments broken by leading the same through two" sets of nip rollers, theforward'set ifeithe set from which the yarn issues;-'bingdriven -underslightly'greater speed than the rear set. These two sets of nip rollersmaybe spaced-from l inch to or more inches apart and the spacing thereofwill determine the length of fiber-into which the smaller denier-orweaker filamentsare; broken. Afterthe yarn leaves the forward nip;rollers it mayhave twist inserted thereinor it maybe wound into apackage and then twisted upona separate device, ,Also, the-yarn thusproduced'may be doubled with a similar yarn, a continuous filament yarn,or a yarn-formed-ofstaple fiber. If desired, some drafting of the yarnmay be accomplished by subjecting the yarn prior to its entrance intothe nip rollers :to the softening action of a solvent. vapor, 'steamorother medium which will allow. the larger denier tor stronger. filaments:to stretch while the smaller denier or weaker filaments are broken anddrafted during the stretching of the'larger filaments.

The continuous filament yarnsmay-be staplized by any suitablemethod. Inplace of themethod described above, which requires stretching of thefilaments to the breaking point, it may be staplized, for instance, byabrading rolls with little or no stretching or drafting; Inthismodifi'cation the first "pair of I rolls which the yarn encountersdoes not form'a truenip. The lower rollfof the pair is milled,'=i. e'.-has a rough surface andthe top rollis comparatively light and bears-downon the yarn with only a ver y light self-lead: The second pair 1 ofi'rolls -whi'ch the yarn encounters forms a definite-nip underrelatively high load and controls the linear speed of the yarn. Thesecond pair of rolls pulls the yarn forward at a linear speedgreaterftha'n the peripheralspeed 0f the milled roll 'of the firstp'air. Inasmuch as this first pair of rolls -is travellingat asur'facespeed less-thanthat-of the yarn and the top roll does not form apositive nip the yarn slips forward and is broken in places, 'which arevariably spaced, on this pair of abradingrolls. The lower denierfilaments break more readily than the coarser filaments;

. v The yarns prior to or afterthe operation which breaks the smallerdenier or weaker filaments may be subjected to any of the processes nowemployed to change the physical "or chemical nature thereof; Forinstance-the yarns may be treated and boiled in water to produce adelustered yarn; they may have sizes-"and lubricants applied thereto,they may have dyes and fugitivetints applied thereto, or they may beotherwise modified. The basic yarn may beof high, medium or low luster,the luster being modifiedjfor example, by the incorporation of pigments, by treatment with boiling soap solution orother aqueous liquorsor by any other method.

Similarly the yarns doubled with the. yarns of the preseri'tinveritionmay be of noi n'i'al luster 'ing them in admixture with other yarns.

or the luster may be suitably modified. The association of lustrous andnon-lustrous yarns or filaments may take place before or after thebreaking of constituent filaments.

The yarns or mixed yarns of the invention may be woven, knitted orotherwise made up into fabrics consisting solely of said yarns orcontain- For example, the yarns may be introduced into the weft or warp,or both, to produce a woven fabric having the appearance of oneconstituted wholly of staple fiber yarn or having pattern "efie'cts withor without differential luster.

The invention is particularly applicable to knitted uent of the fabric.Knitted fabrics made of yarns produced in accordance with this inventionare exceptionally well suited for ladies underwear fabri'csas they havethe appearance of being made of staple-lengthfiber and yet they areextremely: soft and, have high covering power.

As :an'illustration of this invention, but without being limitedthereto, the following examples are given:. e I

Example I A 25%;solution of cellulose acetate dissolved in acetoneisextrude'd'through suitable spinning jets to" produce a yarn. This yarnis formed of one end of an denier 20' filament yarn spun from'onejet'andan end of 85 denier' lfl'filament yarn spun'from'a'nother jet'in the same cabinet. These ends are drawn together at the feed roll andwound on to thesame bobbin producing a yarn of 1'70v denier 60 filamentsand contains about 1 turn per inch of twist; The yarn is then placed ona s'taplizing device and passed .to the two sets of rollers, theabradin'g rollsor the first pair of rolls which the yarn encountersbeing spaced.- about 5" fromthe second pair of rolls, which travels at ahigher speedthan the, first set of rolls, in such a manner thatthe.finer fila'f ments are bruised orabraded and thereby broken into 6.'lengths, whilethe coarser filaments remain substantially continuous.This yarn is then given between 5 and 10 turns per-inch twist, and afabricknitted therefrom by-a" circular knitting operation. The yarn runsexceptionally well-in circular knitting machinesandthe total faults peryard are below 0.08. i I

Cellulose acetate threads formed by spinning a suitable, solution'pfcellulose acetate through jetsis-f'ormedfrom one end of denier- 20fila-; mentyarn and one endof 6,0denien20 filament yarn 'spuniinadjacent cabinetsand adrawnatoe gether at the feed 1 011 i and. wound".on fto the same. bobbin with. aftwistof about 0-.fi -turn per inch. ;lThis yarn is passedfthrough the staplizing device similar to the yarn ofExamplesL :The yarn is then'twi'sted to fr0m'.5 to :10 turns per inchand knitted by circular knitting into a fab'ric.1- .The yarn :runs.exceptionally well in ciiicular-knitting -.machines and thezfabriciproducedz contains 'no'thin places or slub holes..-arid hassubstantially no faults." q .7 I

The above examples are; merelylillustrative of yarns'that may beproducedcin' accordance with this: invention. Where. three sizes: offilaments are: 'employedin building up the; same yarn, for. instance,:all' of the smaller-denier on-weakest filamentsiwill: be ibroken aandtaipartvof the ime-:

I dium' sized filaments may be "broken 'whil'e the coarser filamentswill be substantially continuous. Although this invention is applicableto yarns having two or more sizes of filaments regardless of how theyare formed, I have found it preferable to spin the yarn from one cabinethaving at least two jets therein, each jet having different size holes.This arrangement allows for the use of standard jets in the productionof yarn without the necessity of reaming out a part of the holes of astandard jet.

One arrangement for carrying out my invention will now be described withreference to the accompanying diagrammatic drawing.

The drawing shows a spinning cell I containing two jets 2 and 3 fromwhich bundles of filaments 4 and. 5, each bundle containing filaments ofa denier different than the other, are extruded in a downwarddirectionand are withdrawn from the cell through an opening 6. Thebundles of filaments 4 and 5 are led from opening 6 over a draw roller 7and through pairs of rollers 8, 8 and 9, 9, each pair of which areoperated at different speeds and in such a manner as to break only thefilaments of smaller denier. The combined bundles of filaments, nowcontaining staple fibers, are passed through a guide II on to a suitablecollecting device 12.

.It is to be understood that the foregoing de tailed description ismerely given by way of illustration and that many variations may be madetherein without departing from the spirit of my invention.

7 Having described my invention, what I desire to secure by LettersPatent is:

1. Process for the manufacture of staplized yarn, which comprisesproducing from a solution of cellulosic material a yarn of substantiallycontinuous filaments of at least two different deniers and, whileretaining said filaments in association as a yarn, dividing thefilaments of smaller denier into short lengths and leaving the heavierfilaments in substantially continuous form.

2. Process for the manufacture of staplized yarn, which comprisesproducing from a solution of an organic derivative of cellulose materiala yarn of substantially continuous filaments of at least two differentdeniers and, while retaining said filaments in association as a yarn,dividing the filaments of smaller denier into short lengths and leavingthe heavier filaments in substantially continuous form.

3. Process for the manufacture of staplized yarn, which comprisesproducing from a solution of cellulose acetate material a yarn ofsubstantially continuous filaments of at least two different deniersand, while retaining said filaments in association as a yarn, dividingthe filaments of smaller denier into short lengths and leaving theheavier filaments in substantially continuous form.

4. Process for the manufacture of staplized yarn, which comprisesproducing a yarn from a solution of cellulosic materials havingsubstantially continuous filaments of at least two different. deniersand subjecting the yarn to a strain whereby the smaller denier filamentsare broken and the heavier filaments are left in substantiallycontinuous lengths.

5. Process for the manufacture of staplized yarn, which comprisesproducing a yarn from a solution of an organic derivative of cellulosematerial having substantially continuous filaments of at least twodifferent deniers and subjecting the yarn to a strain whereby thesmaller denier solution of cellulosic material having substantiallycontinuous filaments of at least two different deniers and subjectingthe yarn to a controlled abrading action whereby the smaller denierfilaments are broken and theheavier filaments are left in substantiallycontinuous lengths. 8. Process for the manufacture of 'staplized yarn,which comprises producing .a yarn from a solution of an organicderivative of cellulose material having substantially continuousfilaments of at least two different deniers and subjecting the yarn to acontrolled abrading action whereby the smaller denier filaments arebroken and the heavier filaments are left in substantially con tinuouslengths.

9. Process for the manufacture of staplized yarn, which comprisesproducing a yarn from a solution of cellulose acetate material havingsubstantially continuous filaments of at least two different deniers andsubjecting'the yarn to a controlled abrading action whereby the smallerdenier filaments are broken and the heavier filaments are left insubstantially continuous lengths. l

10. Process for the manufacture of staplized yarn, which comprisesextruding a solution of cellulosic material through two jets havingholes of different sizes and located in the same cabinet, associatingthe extruded material to form a yarn of substantially continuousfilaments of at least two different deniers and, while retaining saidfilaments in association as a yarn, dividing the filaments of smallerdenier into short lengths and leaving the heavier filaments insubstantially continuous form.

11. Process for the manufacture of staplized yarn, which comprisesextruding a solution of an organic derivative of cellulose materialthrough two jets having holes of different sizes and located in the samecabinet, associating the extruded material to form a yarn ofsubstantially continuous filaments of at least two different deniersand, while retaining said filaments in association as a yarn, dividingthe filaments of smaller denier into short lengths and leaving theheavier filaments in substantially continuous form.

12. Process for the manufacture of staplized yarn, which comprisesextruding a solution of cellulose acetate material through two jetshaving holes of different sizes and located in the same cabinet,associating the extruded material to form a yarn of substantiallycontinuous filaments of at least two different deniers and, whileretaining said filaments in association as a yarn, dividing thefilaments of smaller denier into short lengths and leaving the heavierfilaments in substantially continuous form.

13. Process for the manufacture of staplized yarn, which comprisesspinning a solution of an organic derivative of cellulose into a yarn ofsubstantially continuous filaments, spinning a second solution of anorganicderivative of cellulose into 'form. t

a second yarn of substantially continuousffilaments having a heavierdenier than the first yarn, drawing theytwo:yarns' together to form a'u'rntaryyarn and; whileretaining said two yarns together as aunitarytyarn, dividing the filaments ofsmaller denier into shortlengthsand leaving the heavier filamentstin substantially continuous 14.Process for thenmanufacture of "staplized yarn, which comprises(spinning a solution of cellulose acetate into ta yarn of substantially*continuous filaments, spinninga secondsolution of cellulose acetateinto a second yarn of substantially: continuous filaments having aheavier denierthan the firsttyarn,=drawin the two. yarns together toforma unitary yarn and, while retaining said two yarns together as aunitary yarn, dividing the filaments of smaller denier into shortlengths and leavingtherhe'avier filaments in substantially continuousform. 7

15. Process for the manufacture. of staplized yarn, which comprisesspinning a solution of an organic derivative ofcellulose into a yarn ofsubstantially continuous filaments, spinning a second solution of anorganic derivative of cellulose into a second yarn of substantiallycontinuous filaments having a heavier denier than the first yarn,twisting the two yarns together with a twist of about one turn per inchto form a unitary yarn and, while retaining said twoyarns together as aunitary yarn, dividing thefilaments of smaller denier into short lengthsand leaving the heavier filaments in substantially continuous form.

16. Process for the manufacture of staplized yarn, which comprisesspinning a solution of cellulose acetateinto a yarn ofsubstantiallycontinuous filaments; spinning a second solution ofcellulose acetate, into a 'secondyarn of substantially continuousfilaments having a heavier denier than the first yarn, twisting the twoyarns together with a twist of about one turn per inch to form a unitaryyarn and, while retaining said two yarns together as a unitary yarn,dividing-the filaments of smaller denier into short lengths and leavingthe heavier filaments in substantially continuous form. I

'17. Process for the manufacture of staplized yarn, which comprisesspinning a solution of an organic derivative of cellulose into a yarn ofI substantially continuous filaments, spinning a second solution of anorganic derivative of cellulose into a second yarn of substantiallycontinuous filaments having a heavier denier than the first yarn,twisting the. two yarns together with a twist of about one turn per inchto form a unitary yarn and, while retaining said .two yarns together asa unitary yarn, dividing the filaments of smaller denier into shortlengths and leaving the heavier filaments in substantially vtwo yarnstogether as a unitaryyarn, dividing the filaments of smaller denier intoshort lengths and leaving the heavier filaments in substantiallycontinuous form by passing said unitary yarn through the nlps of rotarysurfaces moving at different rates of speed. WILLIAM .WHITEHEAD.

